1. Field of the Invention
The present invention relates to an improvement in a portable chamferring machine which performs chamferring by means of a rotary cutter and, more particularly, to a chamferring machine having a mechanism for moving the rotary cutter axially relative to a workpiece.
2. Description of the Related Art
A conventional chamferring machine for chamferring the side edges of a workpiece by means of a rotary cutter having cutting edges formed on its periphery is disclosed in U.S. Pat. No. 4,655,653. This machine has a main body having at the distal end of which is provided a rotary cutter and includes a guide formed by two orthogonally intersecting guide surfaces which are brought into contact with the surfaces of the workpiece at both sides of the side edge to be chamferred. A crosswise extending hole is formed at the intersection between these guide surfaces such that the cutting edges of the inclined rotary cutter are exposed therethrough.
Because, in the case of conventional chamferring machines, there is a fixed positional relationship between the side edges of the workpieces being chamferred and the rotary cutter, this results in only one portion of the cutting edges performing cutting, which causes comparatively rapid wear thereof. Not only does such rapid wear increase the risk of damage to the cutting portion but, more importantly, necessitates the frequent replacement of the entire rotary cutter, which is both inconvenient and uneconomical.